Thread: Custom Frame
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Unread 30-12-2011, 14:53
Andrew Schreiber Andrew Schreiber is offline
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Re: Custom Frame

Quote:
Originally Posted by squirrel View Post
Mecanum wheels don't like a stiff frame, flexibility is good. They need all the wheels on the floor all the time, or they go off in strange directions.
Quoted for great truthiness.

Mecanum wheels rely on the fact the wheels produce forces in differing directions. These add up to get the desired motion. If you have different weight on each wheel (as you would with a stiff frame on a non-flat surface) you will get drastically changing behavior. It is the same reason you want to ensure that your CG is as balanced as possible as well.

There should be ways of compensating for different loading on your wheels, probably even doing so dynamically by placing load cells above wheel pods but it is hard math for me*. I find it simpler to just let it be sloppy and loose and be careful with my CG.

*I'm sure Ether will come in here and show me an elegant way of doing this but to me it is hard math.
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